U.S. patent application number 15/524592 was filed with the patent office on 2018-10-04 for device and method for monitoring resources in full virtualization system.
The applicant listed for this patent is SOOSAN INT CO., LTD.. Invention is credited to Hoi Chan Jeong, Kyoung Tae Kang, Kwan Jae Lee, Seung Hyun Seo.
Application Number | 20180285138 15/524592 |
Document ID | / |
Family ID | 55355194 |
Filed Date | 2018-10-04 |
United States Patent
Application |
20180285138 |
Kind Code |
A1 |
Jeong; Hoi Chan ; et
al. |
October 4, 2018 |
DEVICE AND METHOD FOR MONITORING RESOURCES IN FULL VIRTUALIZATION
SYSTEM
Abstract
The present invention relates to a device and a method for
monitoring resources in a full virtualization system, the device
and method generating a file table by parsing tile information,
generating a memory table when a memory is allocated, and then
determining whether to execute a command by a process unit with
reference to the file table and the memory table when the command
is generated from a guest operating system or an application such
that a virtual machine monitor is requested to execute the
command.
Inventors: |
Jeong; Hoi Chan; (Seoul,
KR) ; Lee; Kwan Jae; (Seoul, KR) ; Seo; Seung
Hyun; (Seoul, KR) ; Kang; Kyoung Tae; (Seoul,
KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SOOSAN INT CO., LTD. |
Seoul |
|
KR |
|
|
Family ID: |
55355194 |
Appl. No.: |
15/524592 |
Filed: |
November 5, 2015 |
PCT Filed: |
November 5, 2015 |
PCT NO: |
PCT/KR2015/011821 |
371 Date: |
May 4, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G06F 3/0673 20130101;
G06F 2201/865 20130101; G06F 3/0643 20130101; G06F 11/30 20130101;
G06F 12/14 20130101; G06F 11/3051 20130101; G06F 11/302 20130101;
G06F 2009/45583 20130101; G06F 2212/1052 20130101; G06F 11/301
20130101; G06F 12/109 20130101; G06F 2212/251 20130101; G06F 3/0664
20130101; G06F 2212/657 20130101; G06F 3/061 20130101; G06F 9/45558
20130101; G06F 2009/45591 20130101; G06F 12/1483 20130101; G06F
2009/45579 20130101; G06F 3/0619 20130101 |
International
Class: |
G06F 9/455 20060101
G06F009/455; G06F 3/06 20060101 G06F003/06 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 5, 2014 |
KR |
10-2014-0152869 |
Claims
1. A method of monitoring resources in a full virtualization
system, the method comprising: generating a file table by parsing
file information; requesting a virtual machine monitor to execute a
file input/output (I/O) command in response to an occurrence of the
file I/O command in a guest operating system or an application; and
verifying whether a file requested by the file I/O command is
accessible by referring to the file table.
2. The method of claim 1, wherein the verifying comprises emulating
the file I/O command to a format that is verifiable by the virtual
machine monitor through an emulator.
3. The method of claim 1, wherein the file information is at least
one of path information of the file, a block number, and i-node
information.
4. The method of claim 1, wherein the file table includes the file
information and a right to access each piece of the file
information.
5. The method of claim 1, further comprising: executing the file
I/O command when the file requested by the file I/O command is
6. The method of claim 1, further comprising: blocking an access
when the file requested by the file I/O command is verified to be
inaccessible.
7. The method of claim 6, wherein the blocking comprises processing
the file requested by the file I/O command to be displayed as a bad
sector, to be displayed as "0", or to represent a protection
area.
8. The method of claim 1, further comprising: updating the file
table in response to an occurrence of at least one of addition of
the file, deletion of the file, change of the file, and change of
an access right.
9. A method of monitoring resources in a full virtualization
system, the method comprising: generating a file table by parsing
file information; generating a memory table when allocating a
memory; requesting a virtual machine monitor to execute a command
in response to an occurrence of the command in a guest operating
system or an application; verifying a memory area that the command
refers to and verifying a process allocated to the verified memory
area from the memory table; and verifying whether the process has a
right to execute the command by referring to the file table.
10. The method of claim 9, wherein the file information is at least
one of path information of the file, a block number, and i-node
information.
11. The method of claim 9, wherein the file table includes the file
information, accessible process information, and an access
right.
12. The method of claim 9, wherein the memory table includes
virtual machine information, process information, and the memory
area allocated to the process.
13. The method of claim 9, further comprising: executing the
command when the process is verified to have the right to execute
the command.
14. The method of claim 9, further comprising: blocking an access
when the process is verified to not have the right to execute the
command.
15. The method of claim 14, wherein the blocking comprises
processing the file requested by the file I/O command to be
displayed as a bad sector, to be displayed as "0", or to represent
a protection area.
16. The method of claim 9, further comprising: updating the file
table in response to an occurrence of at least one of addition of
the file, deletion of the file, change of the file, change of an
access right, and change of accessible process information.
17. The method of claim 9, further comprising: updating the memory
table in response to allocation, change, and retrieval of the
memory area.
18. A non-transitory computer-readable recording medium storing a
program to implement the method of claim 1.
19. An apparatus for monitoring resources in a full virtualization
system, the apparatus comprising: a file generator configured to
generate a file table by parsing file information; a virtual
machine process configured to request a virtual machine monitor to
execute a file input/output (I/O) command in response to an
occurrence of the file I/O command in a guest operating system or
an application; and the virtual machine monitor configured to
verify whether a file requested by the file I/O command is
accessible by referring to the file table.
20. (canceled)
21. A non-transitory computer-readable recording medium storing a
program to implement the method of claim 9.
Description
TECHNICAL FIELD
[0001] At least one example embodiment relates to monitoring
resources in a full virtualization system, and more particularly,
to monitoring an access to a file and controlling an access from a
virtual machine process based on a file unit by verifying a preset
access right for each file.
TECHNICAL FIELD
[0002] A lexical meaning of "virtualization" is defined as an "act
of processing something unreal or ambiguous based on assumption
that something unreal or ambiguous is a fact or an entity present
in reality.
[0003] Herein, virtualization technology refers to "technology
capable of installing and using a computer operating system without
affecting a system structure or hardware".
[0004] The virtualization technology refers to technology proposed
by IBM in 1970 ties to reduce a space of a main frame and cost at
that time. However, the virtualization technology is currently in
the spotlight by providing compatibility, flexibility, and security
in addition to the cost saving effect. The virtualization
technology may be applicable to various fields, such as a server
virtualization for cloud computing, a desktop virtualization, a
mobile virtualization, and the like.
[0005] A virtualization may be variously classified based on a
configuration method and, generally, may be classified into a full
virtualization and a Para virtualization.
[0006] The full virtualization refers to virtualization technology
that virtualizes hardware and thus, does not require modification
of a kernel.
[0007] On the contrary, the Para virtualization refers to
virtualization technology that partially virtualizes hardware and
needs to modify a guest operating system kernel to fit for an
interface required by a virtual machine monitor (VMM).
[0008] The virtualization technology is used due to its security,
which is based on a relatively high isolation feature of
virtualization. In general, a virtualization environment includes a
virtual machine and a virtual machine monitor or a hypervisor
configured to manage the virtual machine. Each virtual machine is
present in an isolated space. In particular, although a threat
occurs in a virtual machine, the thread does not affect other
virtual machines, excluding the corresponding virtual machine, and
a virtual machine monitor.
[0009] However, security solutions used in an existing physical
machine in a virtualization system have some constraints and a
repetition rate of security threat is on the significant
increase.
[0010] The security solutions have some constraints in the
virtualization system since a plurality of operating systems is
installed in a single virtualization system.
[0011] If hackers attack to access data at an operating system
level using one of the operating systems installed in the
virtualization system, it may be difficult to prevent the
attack.
[0012] Accordingly, there is a need for technology capable of
effectively monitoring and blocking an access to data.
DETAILED DESCRIPTION
Technical Subject
[0013] At least one example embodiment provides an apparatus and
method for monitoring resources in a full virtualization
system.
[0014] At least one example embodiment also provides an apparatus
and method for monitoring an access to a file and controlling an
access from a virtual machine process based on a file unit by
verifying a preset access right for each file in a full
virtualization system.
[0015] At least one example embodiment also provides technology for
generating a file table in which an access right is set for each
file by parsing in advance file information, and controlling an
access to a file by determining whether the file is accessible by
referring to the file table in response to an occurrence of a file
input/output (I/O) command at a virtual machine process level.
[0016] At least one example embodiment also provides technology for
generating a file table in which an access right is set for each
file by parsing in advance file information, generating a memory
table that includes an allocated memory area and process
information when a memory is allocated, and controlling whether to
execute a command by referring to the file table and the memory
table in response to an occurrence of the command at a virtual
machine process level.
Solution
[0017] According to an example embodiment, there is provided a
method of monitoring resources in a full virtualization system, the
method including generating a file table by parsing file
information; requesting a virtual machine monitor to execute a file
input/output (I/O) command in response to an occurrence of the file
I/O command in a guest operating system or an application; and
verifying whether a file requested by the file I/O command is
accessible by referring to the file table.
[0018] Here, the verifying may include emulating the file I/O
command to a format that is verifiable by the virtual machine
monitor through an emulator.
[0019] Here, the file information may be at least one of path
information of the file, a block number, and i-node
information.
[0020] Here, the file table may include the file information and a
right to access each piece of the file information.
[0021] The method of monitoring resources in the full
virtualization system may further include executing the file I/O
command when the file requested by the file I/O command is verified
to be accessible.
[0022] Also, the method of monitoring resources in the full
virtualization system may further include blocking an access when
the file requested by the file I/O command is verified to be
inaccessible.
[0023] Here, the blocking may include processing the file requested
by the file I/O command to be displayed as a bad sector, to be
displayed as "0", or to represent a protection area.
[0024] The method of monitoring resources in the full
virtualization system may further include updating the file table
in response to an occurrence of at least one of addition of the
file, deletion of the file, change of the file, and change of an
access right.
[0025] According to another example embodiment, there is provided a
method of monitoring resources in a full virtualization system, the
method including generating a file table by parsing file
information; generating a memory table when allocating a memory;
requesting a virtual machine monitor to execute a command in
response to an occurrence of the command in a guest operating
system or an application; verifying a memory area that the command
refers to and verifying a process allocated to the verified memory
area from the memory table; and verifying whether the process has a
right to execute the command by referring to the file table.
[0026] Here, the file information may be at least one of path
information of the file, a block number, and i-node
information.
[0027] Here, the file table may include the file information,
accessible process information, and an access right.
[0028] Here, the memory table may include virtual machine
information, process information, and the memory area allocated to
the process.
[0029] The method of monitoring resources in the full
virtualization system may further include executing the command
when the process is verified to have the right to execute the
command.
[0030] Also, the method of monitoring resources in the full
virtualization system may further include blocking an access when
the process is verified to not have the right to execute the
command.
[0031] Here, the blocking may include processing the file requested
by the file I/O command to be displayed as a bad sector, to be
displayed as "0", or to represent a protection area.
[0032] Also, the method of monitoring resources in the full
virtualization system may further include updating the file table
in response to an occurrence of at least one of addition of the
file, deletion of the file, change of the file, change of an access
right, and change of accessible process information.
[0033] Also, the method of monitoring resources in the full
virtualization system may further include updating the memory table
in response to allocation, change, and retrieval of the memory
area.
[0034] According to an example embodiment, there is provided an
apparatus for monitoring resources in a full virtualization system,
the apparatus including a file generator configured to generate a
file table by parsing file information; a virtual machine process
configured to request a virtual machine monitor to execute a file
input/output (I/O) command in response to an occurrence of the file
I/O command in a guest operating system or an application; and the
virtual machine monitor configured to verify whether a file
requested by the file I/O command is accessible by referring to the
file table.
[0035] Here, the virtual machine process may further include an
emulator configured to emulate the file I/O command to a format
that is verifiable by the virtual machine monitor, and the virtual
machine monitor may emulate the file I/O command to a format that
is verifiable by the virtual machine monitor through the
emulator.
[0036] Here, the file information may be at least one of path
information of the file, a block number, and i-node
information.
[0037] Here, the file table may include the file information and a
right to access each piece of the file information.
[0038] Here, the virtual machine monitor may be configured to
execute the file I/O command when the file requested by the file
I/O command is verified to be accessible.
[0039] Here, the virtual machine monitor may be configured to block
an access when the file requested by the file I/O command is
verified to be inaccessible.
[0040] Here, the virtual machine monitor may be configured to
process the file requested by the file I/O command to be displayed
as a bad sector, to be displayed as "0", or to represent a
protection area.
[0041] Here, the file parser may be configured to update the file
table in response to an occurrence of at least one of addition of
the file, deletion of the file, change of the file, and change of
an access right.
[0042] According to another example embodiment, there is provided
an apparatus for monitoring resources in a full virtualization
system, the apparatus including a file parser configured to
generate a file table by parsing file information; a virtual
machine monitor configured to generate a memory table when
allocating a memory; and a virtual machine process configured to
request the virtual machine monitor to execute a command in
response to an occurrence of the command in a guest operating
system or an application. The virtual machine monitor is configured
to verify a memory area that the command refers to, to verify a
process allocated to the verified memory area from the memory
table, and to verify whether the process has a right to execute the
command by referring to the file table.
[0043] Here, the file information may be at least one of path
information of the file, a block number, and i-node
information.
[0044] Here, the file table may include the file information,
accessible process information, and an access right.
[0045] Here, the memory table may include process information and
the memory area allocated to the process.
[0046] Here, the virtual machine monitor may be configured to
execute the command when the process is verified to have the right
to execute the command.
[0047] Here, the virtual machine monitor may be configured to block
an access when the process is verified to not have the right to
execute the command.
[0048] Here, the virtual machine monitor may be configured to
process the file requested by the file I/O command to be displayed
as a bad sector, to be displayed as "0", or to represent a
protection area.
[0049] Here, the file parser may be configured to update the file
table in response to an occurrence of at least one of addition of
addition of the file, deletion of the file, change of the file,
change of an access right, and change of accessible process
information.
[0050] Here, the virtual machine monitor may be configured to
update the memory table in response to allocation, change, and
retrieval of the memory area.
Effect
[0051] Example embodiments relate to technology for generating a
file table by parsing file information, and verifying whether a
file requested by a file input/output (I/O) command is accessible
by referring to the file table when a file I/O command occurs in a
guest operating system or an application and a virtual machine
monitor receives a request for executing the command. Thus, it is
possible to monitor and control an access from a virtual machine
process based on a file unit.
[0052] Also, example embodiments relate to technology for
generating a file table by parsing file information, generating a
memory table when allocating a memory, and determining whether a
file is executable based on a process unit by referring to the file
table and the memory table when a command occurs in a guest
operating system or an application and a virtual machine monitor
receives a request for executing the command Thus, a full
virtualization system may monitor and control resources based on a
process unit.
BRIEF DESCRIPTION OF DRAWINGS
[0053] FIG. 1 is a diagram illustrating a configuration of a full
virtualization system configured to monitor disk resources
according to an example embodiment.
[0054] FIG. 2 illustrates an example of a file table generated to
manage disk resources in a full virtualization system according to
an example embodiment.
[0055] FIG. 3 is a flowchart illustrating a process of monitoring
disk resources in a full virtualization system according to an
example embodiment.
[0056] FIG. 4 is a diagram illustrating a configuration of a full
virtualization system configured to monitor resources of a disk and
a memory according to an example embodiment.
[0057] FIG. 5 illustrates an example of a file table generated to
manage disk resources in a full virtualization system according to
an example embodiment.
[0058] FIG. 6 illustrates an example of a memory table generated to
manage memory resources in a full virtualization system according
to an example embodiment.
[0059] FIG. 7 illustrates a format of a memory allocated based on
the memory table of FIG. 6.
[0060] FIG. 8 is a flowchart illustrating a process of monitoring
resources of a disk and a memory in a full virtualization system
according to an example embodiment.
BEST MODE
[0061] Other aspects and features will be apparent from the
following example embodiments, which are illustrated in the
accompanying figures.
[0062] The example embodiments are described with reference to the
accompanying drawings. In the description of example embodiments,
detailed description of known related structures or functions will
be omitted when it is deemed that such description will cause
ambiguous interpretation of the present disclosure.
[0063] However, the present disclosure is not limited to or
restricted by the example embodiments. Like drawing reference
numerals refer to like elements.
[0064] Hereinafter, an apparatus and method for monitoring
resources of a guest operating system in a full virtualization
system according to an example embodiment is described with
reference to FIGS. 1 through 8.
[0065] FIG. 1 is a diagram illustrating a configuration of a full
virtualization system configured to monitor disk resources
according to an example embodiment.
[0066] Referring to FIG. 1, the full virtualization system includes
a virtual machine (VM) processes 110 and 120, a file parser 130, a
virtual machine monitor (VMM) 140, and a disk 150. Here, the
virtual machine process 110 may include an application (app) 112, a
guest operating system (OS) 114, and an emulator (quick emulator
(QEMU)) 116.
[0067] The file parser 130 generates a file table by parsing file
information stored on the disk 150.
[0068] Here, the file information may be one of path information of
a file, a block number, and i-node information. The file table may
be configured in a format of FIG. 2.
[0069] FIG. 2 illustrates an example of a file table generated to
manage disk resources in a full virtualization system according to
an example embodiment.
[0070] Referring to FIG. 2, the file table may include file
information and a right to access each piece of the file
information. FIG. 2 illustrates a case in which the file
information is an i-node. The file information corresponds to
identification information of blocks that constitute a file.
[0071] Based on the file table of FIG. 2, a guest operating system
or an application executed in a virtual machine process may read
and write a file including blocks #1, 2, and 3, may read only a
file including a block #7, and may block an access to a file
including blocks #9, 10, and 11, and may read and write a file
including blocks #8, 12, 13, and 14.
[0072] The file parser 130 may update the file table in response to
an occurrence of at least one of addition of a file, deletion of
the file, change of the file, and change of an access right.
[0073] In the meantime, the file parser 130 may be configured as a
separate apparatus, may be included in each emulator 116, and may
be included in the virtual machine monitor 140.
[0074] In response to an occurrence of a file input/output (I/O)
command or receiving the file I/O command from the application 112,
the guest operating system 114 requests the virtual machine monitor
140 to execute the file I/O command.
[0075] The emulator 116 emulates the file I/O command to a format
that is verifiable by the virtual machine monitor 140.
[0076] The virtual machine monitor 140 verifies whether the file
I/O command is accessible to a file desired to be accessed by
referring to file table.
[0077] In detail, when the file I/O command is received from the
guest operating system 114 that is included in the virtual machine
process 110, the virtual machine monitor 140 requests the emulator
116 to emulate the file I/O command. When the emulated file I/O
command is received from the emulator 116, the virtual machine
monitor 140 verifies an access right corresponding to a file
requested by the file I/O command from the file table.
[0078] When the file requested by the file I/O command is
accessible as a result of verifying the access right through the
file table, the virtual machine monitor 140 executes the file I/O
command. The virtual machine monitor 140 provides the result to the
guest operating system 114.
[0079] When the file requested by the file I/O command is
inaccessible as a result of verifying the access right through the
file table, the virtual machine monitor 140 blocks an access.
[0080] Here, as a blocking method, the virtual machine monitor 140
may process the file requested by the file I/O command to be
displayed as a bad sector, to be displayed as "0", or to represent
a protection area.
[0081] Hereinafter, a method according to an example embodiment
configured as FIG. 1 is described with reference to FIG. 3.
[0082] FIG. 3 is a flowchart illustrating a process of monitoring
disk resources in a full virtualization system according to an
example embodiment.
[0083] Referring to FIG. 3, in operation 310, the full
virtualization system generates a file table by parsing file
information of files pre-stored on a disk.
[0084] In operation 312, the full virtualization system requests a
virtual machine monitor to execute a file I/O command in response
to an occurrence of the file I/O command in a guest operating
system or an application included in a virtual machine process of
the full virtualization system.
[0085] When a request for executing the file I/O command is
received in operation 314, the virtual machine monitor of the full
virtualization system emulates the file I/O command to a format
that is verifiable by the virtual machine monitor through an
emulator in operation 316.
[0086] In operation 318, the virtual machine monitor of the full
virtualization system verifies whether the file requested by the
file I/O command is accessible by verifying an access right
corresponding to the requested file by referring to the file
table.
[0087] When the file requested by the file I/O command is verified
to be accessible in operation 318, the virtual machine monitor
executes the file I/O command in operation 320.
[0088] In operation 322, a file parser or the virtual machine
monitor updates the file table in response to an occurrence of at
least one of addition of the file, deletion of the file, change of
the file, and change of the access right by the file I/O
command.
[0089] In operation 324, the virtual machine monitor provides a
result of the file I/O command to the guest operating system of the
virtual machine process.
[0090] When the file requested by the file I/O command is verified
to be inaccessible in operation 318, the virtual machine monitor
blocks an access to the corresponding file in operation 326.
[0091] As a method of blocking the access, the virtual machine
monitor may process the file requested by the file I/O command to
be displayed as a bad sector, to be displayed as "0", or to
represent a protection area.
[0092] FIG. 4 is a diagram illustrating a configuration of a full
virtualization system configured to monitor resources of a disk and
a memory according to an example embodiment.
[0093] Referring to FIG. 4, the full virtualization system includes
virtual machine (VM) processes 410 and 420, a file parser 430, a
virtual machine monitor (VMM) 440, and a disk 450. Here, the
virtual machine process 410 may include an application (app) 412, a
guest operating system 414, and an emulator (quick emulator (QEMU))
416.
[0094] The file parser 430 generates a file table by file
information stored on the disk 450.
[0095] Here, the file information may be one of path information of
a file, a block number, and i-node information. The file table may
be configured in a format of FIG. 5.
[0096] FIG. 5 illustrates an example of a file table generated to
manage disk resources in a full virtualization system according to
an example embodiment.
[0097] Referring to FIG. 5, the file table may include process
information, file information, and access right information. FIG. 5
illustrates a case in which the process information is information
indicating a target process and the file information is an i-node.
The file information corresponds to identification information of
blocks that constitute a file.
[0098] Based on the file table of FIG. 5, all of the processes may
read write a file including blocks #1, 2, and 3. Processes A and B
may read only a file including a block #7. All of the processes may
block an access to a file including blocks #9, 10, and 11. Process
C may read and write a file including blocks #8, 12, 13, and
14.
[0099] The file parser 430 may update the file table in response to
an occurrence of at least one of addition of a file, deletion of
the file, change of the file, and change of an access right.
[0100] In the meantime, the file parser 430 may be configured as a
separate apparatus, may be included in each emulator 416, and may
be included in the virtual machine monitor 440.
[0101] When a command having no right occurs or when a command
having no right is received from the application 412, the guest
operating system 414 requests the virtual machine monitor 440 to
execute the command.
[0102] That is, when the guest operating system 414 or the
application 412 being executed in the guest operating system 414 is
to execute the command having no right, the virtual machine monitor
440 executes the command in lieu thereof.
[0103] The emulator 416 emulates the command to a format that is
verifiable by the virtual machine monitor 440.
[0104] When the received command needs to be emulated, the virtual
machine monitor 440 may request the emulator 416 to emulate the
command.
[0105] When the application 412 and the guest operating system 414
executed in the virtual machine process are executed in the guest
operating system 414, the virtual machine monitor 440 may allocate
a memory and may generate allocated memory information as a memory
table and manage the memory table.
[0106] FIG. 6 illustrates an example of a memory table generated to
manage memory resources in a full virtualization system according
to an example embodiment.
[0107] Referring to FIG. 6, the memory table may include virtual
machine information, process information, and a memory area
allocated to a process.
[0108] FIG. 7 illustrates a format of a memory allocated based on
the memory table of FIG. 6.
[0109] Referring to FIG. 7, similar to the memory table of FIG. 6,
it can be verified that 1 to 8 of a memory are allocated to a guest
machine process A.
[0110] Here, 1 and 2 of the memory is allocated to a process A, 3
of the memory is allocated to a process B, 4 and 5 of the memory
are allocated to a process C, and 6, 7 and 8 of the memory are
allocated to the guest operating system 414.
[0111] The virtual machine monitor 440 determines whether a command
is executable by referring to a memory area that the command refers
to, the memory table, and the file table.
[0112] In detail, the virtual machine monitor 440 verifies the
memory area that the command refers to, verifies a process
allocated to the verified memory area from the memory table,
verifies a right to access a corresponding file for each process by
referring to the file table, and verifies whether the process has a
right to execute the command.
[0113] Hereinafter, a method of verifying, by the virtual machine
monitor 440, the memory area that the command refers to is
described. For example, if the command is a read command, it
follows as:
[0114] read (block #7, memory 1)
[0115] The above command is a command to read content stored on a
block 7 of a disk to a number 1 memory area.
[0116] write (block #9, memory 5)
[0117] The above command is a command to store content included in
a number 5 memory area on a block 9 of the disk.
[0118] In the aforementioned read command, the memory area is the
number 1 memory area. In the aforementioned write command, the
memory area is the number 5 memory area.
[0119] Whether the read command and the write command are
executable may be verified by referring to the file table of FIG. 5
and the memory table of FIG. 6.
[0120] It can be verified from the memory table that the process A
of the virtual machine process A is a process allocated to the
number 1 memory area corresponding to the memory area of the read
command. It can be verified from the file table that the block #7
of the file desired to be read by the read command has a read
access right with respect to the process A.
[0121] Accordingly, it can be verified from the file table of FIG.
5 and the memory table of FIG. 6 that read (block #7, memory 1) is
an executable command.
[0122] As another example, it can be verified from the memory table
that the process C of the virtual machine process A is a process
allocated to the number 5 memory area corresponding to the memory
area of the write command It can be verified from the file table
that block #9 of the disk to be written by the write command is
hidden information with respect to all of the processes.
[0123] Accordingly, it can be verified from the file table of FIG.
5 and the memory table of FIG. 6 that write (block #9, memory 5) is
not an executable command
[0124] In the meantime, when a file is to be modified to prevent
modification of the file by a command that does not refer to a
memory, whether to modify the file may be determined based on an
access right of the file table by referring to only the file
table.
[0125] For example, if the command is delete and a process cannot
be determined by referring to the memory table, the virtual machine
monitor 440 may determine whether to execute the command by
verifying an access right preset to a corresponding file when the
process cannot be determined.
[0126] When a process having a right to read a specific file is to
read the specific file and to modify the read file on a memory, the
virtual machine monitor 440 may verify an access right of the
process having with respect to the corresponding file by referring
to the file table and may prevent modification on the memory.
[0127] If the process has a right to execute a command, the virtual
machine monitor 440 executes the command The virtual machine
monitor 440 provides an execution result to the guest operating
system 414.
[0128] The virtual machine monitor 440 may update the memory table
in response to allocation, change, and retrieval of the memory
area. When the memory area is allocated, changed, and retrieved,
the virtual machine monitor 440 may update the memory table. In
addition, when a change occurs in the memory area in response to an
operation of an operating system, the virtual machine monitor 440
may update the memory table.
[0129] If the process does not have the right to execute the
command, the virtual machine monitor 440 blocks an access to the
corresponding file.
[0130] Here, as a method of blocking the access, the virtual
machine monitor 440 may process the file requested by the file I/O
command to be displayed as a bad sector, to be displayed as "0", or
to represent a protection area.
[0131] Hereinafter, a method according to the present disclosure
configured as FIG. 4 is described with reference to FIG. 8.
[0132] FIG. 8 is a flowchart illustrating a process of monitoring
resources of a disk and a memory in a full virtualization system
according to an example embodiment.
[0133] Referring to FIG. 8, in operation 810, the full
virtualization system generates a file table by parsing file
information of files pre-stored on a disk.
[0134] In operation 812, when a guest operating system and an
application are executed, a virtual machine monitor of the full
virtualization system allocates a memory and generates memory
information into a memory table.
[0135] When a command occurs in the guest operating system or the
application in operation 814, the virtual machine monitor receives
a request for executing the command in operation 816.
[0136] In operation 818, the virtual machine monitor verifies a
memory area that the command refers to and verifies a process that
is allocated to the memory area by referring to the memory
table.
[0137] In operation 820, the virtual machine monitor verifies
whether the process has a right to execute the command by referring
to the file table.
[0138] When the process is verified to have the right to execute
the command in operation 820, the virtual machine monitor executes
the command in operation 822.
[0139] In operation 824, if necessary, the virtual machine monitor
may update the file table and the memory table.
[0140] In response to an occurrence of at least one of addition of
a file, deletion of the file, change of the file, change of an
access right, and change of process information accessible to the
file, the virtual machine monitor may update the file table in
operation 824. Also, in response to allocation, change, and
retrieval of the memory area, the virtual machine monitor may
update the memory table in operation 824. In addition, when a
change occurs in the memory area in response to an operation of an
operating system, the virtual machine monitor may update the memory
table. That is, the virtual machine monitor may update the memory
table when the memory area is allocated or retrieved, or when
content stored in the memory is modified, and may also update the
memory table when a location of the memory area is changed.
Accordingly, update of the memory table may be performed at any
time in addition to a point in time corresponding to operation
824.
[0141] In operation 826, the virtual machine monitor 440 may
provide a corresponding result to the guest operating system of the
virtual machine process.
[0142] When the process is verified to not have the right to
execute the command in operation 820, the virtual machine monitor
blocks an access to the file.
[0143] Here, as a method of blocking the access, the virtual
machine monitor may process the file requested by the file I/O
command to be displayed as a bad sector, to be displayed as "0", or
to represent a protection area.
[0144] The method of monitoring resources of the guest operating
system in the full virtualization system according to example
embodiments may be recorded in non-transitory computer-readable
recording media in a form of program instructions executable
through a variety of computer devices. The media may include, alone
or in combination with the program instructions, data files, data
structures, and the like. The program instructions recorded on the
media may be those specially designed and constructed for the
purposes of example embodiments, or they may be of the kind
well-known and available to those having skill in the computer
software arts. Examples of the non-transitory computer-readable
media include magnetic media such as hard disks, floppy disks, and
magnetic tape; optical media such as, CD-ROM and DVD;
magneto-optical media such as optical media and floptical disks;
and hardware devices that are specially configured to store and
perform program instructions, such as ROM, RAM, flash memory, and
the like. Examples of program instructions include both machine
code, such as produced by a compiler a high language code that may
be executed by the computer using an interpreter. The
above-described hardware devices may be configured as one or more
software modules in order to perform the operations of the example
embodiments, or vice versa.
[0145] Although the description is made with reference to some
example embodiments and drawings, they are provided only to assist
in a comprehensive understanding of the present disclosure. Thus,
the present disclosure is not limited to the example embodiments
and it will be apparent to those skilled in the art that various
modifications and changes may be made from the description.
[0146] Therefore, the scope of the disclosure is defined not by the
example embodiments but by the claims and their equivalents, and
all variations within the scope of the claims and their equivalents
are to be construed as being included in the disclosure.
* * * * *